Crude prices have plunged by two-thirds since mid-2014 as soaring output from the Organization of the Petroleum Exporting Countries, Russia and the United States led to a global surplus of between half a million and 2 million barrels per day.

This caused the shares of oil companies such as BP and Total to fall, while British mining stocks also slid lower as metal prices fell due to persistent concerns about a slowdown in China, the world's biggest consumer of metals.

Spreadex analyst Connor Campbell added that a warning by the head of the International Monetary Fund in a newspaper column of disappointing global economic growth next year was adding further pressure on the markets.

Britain's FTSE is down around 4 percent since the start of 2015, having lost ground from a record high reached in April.

However, stock markets in continental Europe have fared better, thanks partly to economic stimulus measures from the European Central Bank.

The FTSEurofirst 300 is up around 6 percent in 2015, while the DAX is up 10 percent.